The present invention relates to a rear vehicle-body structure of a vehicle, and in particular, relates to the rear vehicle-body structure of the vehicle comprising a pillar reinforcement and a reinforcing member connecting an outside portion, in the width direction of the vehicle, of a side panel inner and a rear wheel house.
Conventionally, a suspension of the vehicle is provided with a damper to damp (suppress) vibrations and impacts during the vehicle's traveling for ensuring the maneuverability and stability of the vehicle operated by a driver. This damper is arranged to slant such that an upper side therefore is positioned relatively inward compared to a lower side thereof, and its upper end is supported at a suspension housing (suspension tower) which is formed above the wheel house. Accordingly, an inward-component of a damper load acting on the suspension housing in a vertical direction acts on a vehicle body, so that there is a problem in that the above-described inward-component of the damper load may cause the side panel inner located near the suspension housing to fall down inward, i.e., there may occur a so-called inward falling-down problem.
A rear suspension housing at a rear portion of the vehicle body is provided at a position which is located on a vehicle-compartment lower side near a rear pillar portion which is provided at the side panel inner. Accordingly, the above-described inward falling-down of the side panel inner is prevented by transmitted the above-described damper load vertically acting on the rear suspension housing to a vehicle-body reinforcing member, such as a roof rail member, via the rear pillar portion which forms an inside wall of a passenger's ingress/egress opening, thereby dispersing the load (the inward-component of the damper load) concentrating at the side panel inner (rear pillar portion).
A rear vehicle-body structure of a vehicle disclosed in Japanese Patent Laid-Open Publication No. 2013-233855 is configured, as show in FIG. 10, such that a front edge portion and a rear edge portion of a pillar reinforcement 51 which extends upward from a front-side upper portion of a rear wheel house 50 are joined to a pillar portion 53 of a side panel inner 52, respectively, the pillar reinforcement 51 is joined to a reinforcing member 54 which connects the side panel inner 52 and the rear wheel house 50 at its extension portion 51a, a closed cross section 55 is formed by an upper edge portion, a front edge portion, and a rear edge portion of the reinforcing member 54 which are respectively joined to the side panel inner 52, and there is provided a foamed adhesive having a base portion which is positioned in the closed cross section 55 and a first protrusion portion 57 which protrudes out of a first hole portion 56 which is formed a front end of the upper edge portion of the reinforcing member 54 and joins the reinforcing member 54 and the pillar reinforcement 51 together thereby.
According to the rear vehicle-body structure of the vehicle of the above-described patent document, since the reinforcing member 54 and the pillar reinforcement 51 are joined together via the first protrusion portion 57 of the foamed adhesive, it can be restrained for a joining portion of the reinforcing member 54 and the pillar reinforcement 51 to deform, so that the damper load inputted from the damper can be efficiently transmitted to the pillar portion 53 which is continuous to the roof rail, thereby improving the torsional rigidity of the vertical and lateral directions of the vehicle body. However, in a case in which a wheel base is designed to be long from a vehicle-design requirement, a distance between the damper and the pillar portion becomes so long that it becomes difficult to perform the load-transmission function properly. Consequently, there is a concern that torsional deformation of the vehicle as a whole becomes so large that increasing the thickness of steel plates or adding other reinforcing members may be necessary in order to prevent the above-described inward falling-down of the side panel inner.